//obtain depth image
DepthMetaData depthMD;
g_DepthGenerator.GetMetaData(depthMD);
const XnDepthPixel* g_Depth = depthMD.Data();
cv::Mat DepthBuf(480,640,CV_16UC1,(unsigned char*)g_Depth);
//To display the depth image you probably would want to normalize it to 0-255 range first


//obtain rgb image
ImageMetaData ImageMD;
g_ImageGenerator.GetMetaData(ImageMD);
const XnUInt8* g_Img =ImageMD.Data();
cv::Mat ImgBuf(480,640,CV_8UC3,(unsigned short*)g_Img);
cv::Mat ImgBuf2;
cv::cvtColor(ImgBuf,ImgBuf2,CV_RGB2BGR);